Process of making articles of celluloid and similar material



March 31. 1925. 1,531,504

F. T. ROBERTS PROCESS 0F HAKING ARTICLES OF CELLULOID AND SIMILARMATERIAL Filed July 11, 1921 3 Sheets-Shea?l l f Y /A Arrozem 1,531,504v F. T. ROBERTS und .my 11, 1921A :s sheets-sheet 2 )lf2 O March31,1925.

PROCESS 0F IIAKING ARTICLES OF CELLULQID AND SIMILAR MATERIAL March 31.1925. l 1,531,504 F. T. ROBERTS PROCESS 0F AXIHG'ARTICLES 0F CELLULOIDAND SIMILAR MATERIAL Filed July 11, 1921 3 Sheets-Sheet 3 45' 3r/0000000 00 :0000000000 u I i 0000000 00 0000000000 0 0000000 00|0000000000 W 0000000 00 0000000000 0000000 00 :0000000000 u l H 000000000 [0000000000 000000 00 ;0000000000 000000 00i l000000000 M n 0000000001 .0000000000 OOQO @I 0 00009900 .WZNPOE 10 scription, referencePatented Mar. 31, 1925.

UNITED STATES PATENT oFFlcE. N

Fm THOMAS ROBERTS, OF PIIILADELPHIA, PENNSYLVANIA, ASSIGNOR TO PARA-LIOU'NT RUBBER CONSOLIDATED, INCL, OF TUOKAHOE, NEW YORK, A CORPORATIONF DELAWARE PROCESS OF MAKING ARTICLES OF GELL'ULOID VAND SIMILARMATERIAL.

Application led J'uly 11, 1921. Serial No. 483,703.

To all whom it may com'em:

Be it known that Ij, FRED THOMAS RoB- nRTs, a citizen of the UnitedStates, residin at Philadelphia, in the county of Philade phia and Statof Pennsylvania, have invented acertain new and useful Improve.

ment 'in Processes .of Making Articles of Celluloid and SimilarMaterial, of which the following is a full clear, and exact debeing hadAto the accompanymg drawings. v

The object of this invention is to provide for the rapid and economicalformation of hollow articles from sheets of celluloid or similarmaterial.

A 'characteristic of the invention is' that the material is renderedplastic and-while in that condition is seated by fluid pressure in m'oldcavities, doing away with the necessity of male and female molds and theconsequent requirement for accurate adjustment between the two toprovide the proper thick- 'nessof wall. In the preferred manner ofcarrying out my invention I use steam as both the softening means andthe means for supplying fluid pressure to seat the article,

j vthus enabling the'o'peration to be carriedI out simply andeconom1cally. A feature of the invention provides for first renderingthe sheet of Celluloid plastic then shaping it to. form the article and.finally cooling it.

AA11 additional feature of the invention is the provision whereby acelluloid sheet is not only heated and forced into a suitable mold cavtto form the article and then cooled, but t e article is also severed'from the sheet and the raw edges finished."

' Further and additional objects will be ap- 40 parent from thefollowing description, taken 4in connection with the accompanyingdrawings, wherein Fig. 1 is a view showing a porvtion of a moldapparatus used in carrying out my rocess wit the mold membersvseparated, e'steam chest being removed from between the mold members;Fig. 2 is a sectional view showing themold members after the same hasbeen brought together with the steam chest in position; Fig. 3 is a viewsimilar to Fig. 2, showing the Celluloid forced to its seat by steampressure; Fig. Ll'is a sectional vview showing the step whereby theformed articles are cooled; Fig. 5 is a fragmentary sectional viewshowmg the mold members after the steam chest has been removed; ig. 6 isi sectional view showing the mold members brought together upon a hotplate; Fig. 7 is a sectional detail showing the manner of severingtheindividual articles from the sheet; Fig. 8 is a sectional 60 'viewshowing the hot plate removed. Fig.

9'is a diagrammatic plan illustrating the piping for conveying steam andwater to the steam chest and hot plate and for draining them; Fig. 10'isa cross section of the three- 6F way valve shown in Fig. 9.

vReferring to the drawings by reference characters, I have shown at 10the base of a mold plate provided with a plurality of individual moldmembers having cavities 11. The mold cavities are shown as separated bysuitable spacing blocks 12.

An aperture 14 is provided in the lower vportion of eachwmold cavity andthis aperture communicates with a channel 16 which 75 may be ventedtothe atmosphere. The upper end of each mold cavity may7 be providedwith a cutting edge'17,-as shown for a purpose to be later described.

The lower mold memberA, Fi 1, may rest upon the bead of, a suitableydraulic press, while the upper member B may be secured opposite theportion A. Any suitable type of press may be used, for instance the oneshown in my prior Patent, No. 1,201,- 503, patented Oct. 17,1916.

Cooperating with the -mold members, I have Shown a suitable .steam chest20. This steam chest comprises upper and lowercavities 21 and 22, eachofwhich can be placed in 90 mold cavities. .Upon t three-wayvalveadapted 'to couple any of these conduits with a iexibl'e pi e 44leading to the chambers v21 and 22 o the steam chest. 45 vindicates ableeder or pet cock connected with each of these chambers.

My process may be carried out in the' followingmanner. A sheet ofcelluloid or similar material v25 is placed over the lower series ofmold cavitieswith the edges thereof extending approximateliylI to theedge of said e upper surface of the steam chest 20, I place a slmilarsheet of material. This being done the steam chest is moved between theopposite mold mem- -aperture 14 and channel 16 to the atmosphere.

When all of the individual articleshave been seated in the moldcavities, water is nel 21 turned into the channels 21 and 22, condensingthe steam and at the same time serving to cool the celluloid articlesformed therein. It will be` noted that at this stage ofv the process thevindividual articles which have been formed are united to the sheet attheir topv surfaces and in order to separate them from individualarticles the following step may be taken. The press is operated toseparate the mold members after which the steam chest is withdrawn. Ahot plate 30 is thereafter inserted between the mold members. The h otplate 30 is provided on its upper and ilower surfacew 1th an annularchannel 31, said vchannel terminating in an outwardly spaced 'roundedgroove 32.

The" oove 32 is separated from the chanya cutting edge 33. This cuttinedge 33 coacts withthe cutting edge 1g carriedby the individual moldmembers 11 yso that when the press is operated and. the

mold plates areA forced upon `the hotplate the latter serves to severeach indi/@Qual hollow article about its periphery. The hot plate 30 mayhave` depressions 34 coaxial with the mold cavities lfor the receptio"of the water in the lower containers which lis displaced by thero'ecremove the water from the lower set of articlesv before the beadingof the edge,

the lower mold may be removed and inverted,` the adherence of the said.material to the mold surface allowing such operation.

place between If it is\des1r to.4

it and also to vent it. Fig. 9 illustratesl at 50 a .iiexible pipeconnected with a hot plate and leading to a three-way valve 51 whichconnects with a steam line 52, water line 53 or drain 54. 55 indicates ableeder or pet cock on the hot plate. The valves 43 and 51 may be of anysuitable form. They may be substantially identical and have theconstruction shown in Fig. 10 wherein indicates the casing, 61 a valveplug and 62 a passageway through it.

The hot plate being suliiciently heated by the steam within it, isbrought into contact with the annular edges bf the seated material andco-operates with the cutting edges on the mold members to sever thematerial. At the same time the heat renders such material in this regionmore or less plastic so that the surplus celluloid is forced into thegroove 32, thus a bead or protuberance ispformed about the periphery ofthe hollow articles.

After the articles have been severed water isl turned into the hot plateto cool the same, and after being suiiiciently cooled the mold membersare separated, the hot plate withdrawn and the finished articles areremoved, as shown in Fig. 8.

.lt should be noted that the vents from the vample timefor the removalof the steam chest and hot plate and the draining of the article beforematerial separationv takes the seated stock and the mold surface.

The process described ,ma be used for manufacturing a at vnum er ofhollow articles. I have s own/ it in the drawings as adapted to makea/hollow celluloid article, fsuch vas a thimble, for exam le, al1

thoug his is' only illustrative o of the uses of myf recess.

Having lthus yj' escribed my` invention what I claim as new' is:

1. The process of making hollow celluv many loid articles which consistsin irst renderl i ling a sheet of celluloid plastic, then fore? ing saidcelluloid sheet against the wall of a mold cavity to make a yhollowarticle, cooling said celluloid sheet, and thereafter severing thesurplus stock from the edge of said article while retained in the samemold cavity.

it plastic and at the same time causi loid articles which consists ofhea-ting and simultaneously seating the celluloid iny a mold cavity toform an article, coolin said article, reheating a portion 'of' saiarticle, severing, the surplus stock about the 'periphery of thearticle, and reforming th article adjacent the severing line.

4. The process of makin celluloid articles which consists in rst heatinga sheet of celluloid, then forcing said celluloid sheet into a mold4cavity to form an article, cooling said article and forming a bead u onthe periphery of said article.

5'. T e process of making hollow celluloid articles which consists infirst heating a sheet of celluloid, then vforcing a portion o saidcelluloid sheet into a mold cavity to form an article, cooling saidcelluloid sheet, thereafter severing the stock from the edge of saidarticle, in a mold cavity, and thereafter reheating a portion only ofthe article while i't remains 1n such cavit 6. The rocess of makinghollow celluloid articles w ichv consists of heating a sheet ofcelluloid and forming an' article therefrom, cooling said article,reheating a portion only of said article, and reforming a part of thearticle.

7. The process of making hollow celluloid articles whichy consists infirst heating a sheet of celluloid, th'en forcing said cellu-- Y 'd anumber of celluloid articles w ich consists in first heating a sheet ofcelluloid.

loid sheet into a mold cavity, cooling sal celluloid sheet and .severingthe surplus stock from the edge ofsaid article, and then forming a beadadjacent' the severing line.

8. The process of making hollow cellu,

loid articles which consists in first, rendering plastic all of thecelluloid from which the article in a mold is to be made, forming thearticle, causing the celluloid to become dense while in the same mold,then causing a portion only of the 'formed article to become plastic,and then finishing the article while in the same mold.

9. The process of making hollow celluloid articles which consists inseating acelluloid sheet over a steam chest, bringing said sheet beneatha mold cavity, subjecting said sheet to the action ofsteam wherebytomake it to seat in said cavity subsequently -coo ing said seated sheet,and then cutting the surplus stock away from the article and at'thesam'e time heating the4 edge of the article to smooth it.

10. The process of making hollow celluloid larticles. which consists inseating a celluloid sheet over a mold cavity, subjecting said sheet tothe action of steam whereby to make it plastic and at the same time tocause it to seat in said cavity, subjecting said seated sheet to coolingwater, removing the cooling water, heating the riphery of the formedarticle and finishrng the article.

11. The process of making hollow'celluloid articles which consists inseating a celluloid sheet over a mold cavity, rendering saidsheetplastic and at the same time causing it to seat in said cavity, subjecting said seated sheet to cooling water, removin the cooling` water,reheating the forme articley and at the same time severing said articlefrom the sheet.

12. The process of making hollow cellu-n loid articles lwhich consistsin seatinl a celluloid'sheet over a mold cavity, vholin said sheetadjacent the sides of said mol cavity, subjecting said sheet to theaction of steam whereby to make itV plastic'vand at f the same timev tocause it tobe forced by the steam to seat in said cavity, subjectingsaid seated sheet to cooling water, removing the cooling water, heatinga portion of the lformed article and at the same time severing thearticle from thesheet, forming a bead at the periphery and then coolingthe beaded part.

13. The process of making hollowv cellu-y loid articles which consistsin first rendering a sheet of celluloid lastic then forcing the plasticsheet by uid pressure into a mold cavity, and thereafter formin a beadupon the periphery of said ho ow article. 4

14. The process of simultaneousl making plus stock about the peripheryof the'v articles and reforming the articles adjacent the severing lme.

16. The process of making celluloid articles which consists in. placinga sheet of celluloid stock over a cavita mold member having cuttingedges, heating said stock to render it plastic, pneumatlcally said stockin the m o.`d cavity, coolingsai seated stock, and brin gingv thereaftera `plate having a cutting edge into vconjunction with the first cuttiigedge to sever the stock.

17. The process of making celluloid articles which consists in placmg asheet of Vcelluloid stock over a cavitary mold member lll v4;:,zssnisolifY having' cutting heatiix said stock to to sever the vstockandv to, cal'ise the said render it. la'stlc, pneumatica y seating saidgroove to form a wbead on the periphery of s stock in t e mold cavity,cooling said seated the` hollow articl y stck, reheating. a portion ofsaid heated In testimony whereof, I' hereunto aixv- I .stock,bringing a.hot Plate having a cutting my signature. j edge and a groove adlacentthe cutting edge "f t y into conjunction with the first cutting 'edge- Ay FRED THOMAS ROBERTS,

